calse aclse clase lcase alcse lacse casle acsle csale scale ascle sacle clsae lcsae cslae sclae lscae slcae alsce lasce aslce salce lsace slace cales acles claes lcaes alces laces caels acels ceals ecals aecls eacls cleas lceas celas eclas lecas elcas alecs laecs aelcs ealcs leacs elacs casel acsel csael scael ascel sacel caesl acesl ceasl ecasl aecsl eacsl cseal sceal cesal ecsal secal escal asecl saecl aescl eascl seacl esacl clsea lcsea cslea sclea lscea slcea clesa lcesa celsa eclsa lecsa elcsa csela scela cesla ecsla secla escla lseca sleca lesca elsca selca eslca alsec lasec aslec salec lsaec slaec alesc laesc aelsc ealsc leasc elasc aselc saelc aeslc easlc sealc esalc lseac sleac lesac elsac selac eslac
Note: these 'words' (valid or invalid) are all the permutations of the word calse. These words are obtained by scrambling the letters in calse.